If evolution is true, and if life on Earth originated in water, then there must have once been fish species possessing primitive limbs, which enabled them to spend some part of their lives on land. And these species, in turn, must be the ancestors of four-limbed, land-living vertebrates like us.

Sure enough, in 2004, scientists found one of those transitional species: Tiktaalik roseae, a 375 million-year-old Devonian period specimen discovered in the Canadian Arctic by paleontologist Neil Shubin and his colleagues.

"It has a neck," says Shubin, a professor at the University of Chicago. "No fish has a neck. And you know what? When you look inside the fin, and you take off those fin rays, you find an upper arm bone, a forearm, and a wrist." Tiktaalik, Shubin has observed, was a fish capable of doing a push-up. It had both lungs and gills. In sum, it's quite the transitional form.

Shubin's bestselling book about his discovery, Your Inner Fish: A Journey Into the 3.5-Billion-Year History of the Human Body, uses the example of Tiktaalik and other evolutionary evidence to trace how our own bodies share similar structures not only with close relatives like chimpanzees or orangutans, but indeed, with far more distant relatives like fish.

And now, PBS has adapted Your Inner Fish as a three-part series.

But there's a great irony: When it comes to the melting Arctic, what's good for petroleum geologists is also pretty good for paleontologists, Shubin admits. "You look at the aerial photos, that were taken in 1959, and you can compare them to the aerial photos today, well, there's more rock to look at," he says. Glacial retreats may be a global disaster, but there's no denying they're a scientific opportunity.

All of which means: Those who deny climate change, and through their denial, help to worsen it...well, at least they're giving us more evidence for evolution.

Some smell that way to? I can see where others do have that fish look in their beadie ,big eyes,slimy,scales,avoid the fish hook.OF course "special people"see things differently sometimes thru their eyes!